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Comment by k4ch0w | Hacker News Reader

Macros, Macros, Macros. These are a game changer when editing large files. Use the `q` key and followed by any letter you like, I default to `a`. Perform some action, like deleting a line, appending to the start of a line, or searching for a word then deleting it. Press `esc`, then type in the number of times you want to repeat the action, followed by `@` and the letter you chose. I.E `10@a` and it will perform that action 10 times.

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Also fun: macros can call themselves. So if you want to repeat something across a whole file, it's sometimes easiest to write an infinitely recursive macro and let it error when it bumps up against the bottom of the file.

Vim can be great for quickly doing tedious text transformations. Far easier to get right than doing it the 'proper way' with a script in Python/Perl/whatever.

To do something like scan through a JSON or XML document and split a 'name' field/tag into 'firstName'/'lastName', Vim is the tool I'd reach for.

I think of it as 'cursor-oriented programming', but what I do with it isn't really programming, it's generally of the pattern of 1. Find start of pattern 2. Transform pattern 3. GOTO 1

Or at worst, the decorate/sort/undecorate pattern.

But it boils down to repeatedly applying a macro.

A useful thing to know when using macros is that the letter you press after `q` is just the register in which Vim stores the macro. Registers are also used when copying and pasting. As such, if you want to edit a macro, you can just paste it into a new buffer (e.g., `"ap` for register `a`), edit it as you wish, then copy it back into that register (`:%y a`). You can even use this method to write macros from scratch, rather than recording them first.

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